Rare Radiative B Decays in Standard Model and Beyond

The Standard Model is a well-testified theory via different experimentation, but still, there are some open issues in the theory. To address such issues, researchers explore the theory beyond the Standard Model. We study various channels of Higgs decay and compute their decay rate. Further, we study the radiative rare B decay in the Standard Model and the calculation of the Wilson coefficient is performed explicitly. The new physics usually appears at the loop level. We discuss an extension of the Standard Model by adding vector-like particles. These vector-like particles have no contribution in Higgs decays, Higgs is substituted by gauge singlet in the di-photon resonance. By grasping the idea of di-photon resonance we apply it to Wilson coefficient to calculate the penguin diagrams, where the Standard Model particles are substituted by vector-like particles and gauge singlet to probe new Physics.